Zhao Ruobing, Shea Kenneth J
Department of Chemistry, University of California, Irvine, Irvine, California 92697, United States.
ACS Macro Lett. 2015 May 19;4(5):584-587. doi: 10.1021/acsmacrolett.5b00218. Epub 2015 May 6.
We report the first synthesis of a gradient methylidene-ethylidene copolymer via a living C1 polymerization. The copolymer has a similar chemical structure as the corresponding ethylene-propylene copolymer. To achieve this goal a new and convenient source of the ethylide monomer, diethylsulfoxonium ethylide, was developed for the introduction of the methyl branch in the polymer backbone. The gradient copolymer contains a gradual change of instantaneous methyl branch content from 0% on one end of the polymer chain to 63% on the other end. Thermal analysis revealed that the gradient copolymers have a narrow glass transition temperature range with values intermediate between those of linear polyethylene and atactic polypropylene.
我们报道了通过活性C1聚合首次合成梯度亚甲基-亚乙基共聚物。该共聚物具有与相应的乙烯-丙烯共聚物相似的化学结构。为实现这一目标，开发了一种新型且便捷的亚乙基单体来源——二乙基亚砜亚乙基，用于在聚合物主链中引入甲基支链。该梯度共聚物的瞬时甲基支链含量从聚合物链一端的0%逐渐变化到另一端的63%。热分析表明，梯度共聚物具有较窄的玻璃化转变温度范围，其值介于线性聚乙烯和无规聚丙烯之间。
